Pencil sharpener



P 1950 l. e. A. LJUNGGRVEN 2,523,382

PENCIL SHARPENER Filed Dec. 21, 1946 a 7.92 24 A? 29 c I m L as 6 24 o 4 I I0 9 g A TTORNE Y5 Patented Sept, 26, 195

UNITED STATES- PATIENT OFFICE ivan Georg Sweden,

Application December 21, 1946, Serial No. 717,688

In Sweden October 30, 1944 In the sharpening of pencils in pencil sharpener's, a certain cautiousness must be observed to avoid the breaking of the point of the pencil during continued operation upon the same after the sharpening of the lead has been completed. Therefore the sharpening of the pencil will take a longer time than would otherwise be necessary, without the risk of the breaking of the readysharpened point being entirely eliminated. The present invention has for its object to obviate this disadvantage, and principally consists in that the pencil sharpener is provided with a signalling means activated by the influence of the pencil or the point thereof, when the latter comes into thepos'ition in which the sharpening of the pencil is completed. The signalling means may be of any suitable kind, for instance of the type giving an acoustic signal. Preferably, however, acoustic signalling means is used in the form of a bell, the signalling mechanism of which is activated or triggered in a certain position of the pencil or the point thereof, the arrangement being preferably such that the signalling mechanism is actuated from the driving means of the machine to give a signal.

The invention will be described more closely with reference to the accompanying drawing, which illustrates a manually operable pencil sharpener provided with a signalling means according to the invention. Fig. 1 is a cross section through the machine, and Fig. 2 shows a section through the portion of the machine on which the bell and the appertaining actuating device are arranged. Fig. 3 is a section on line 3-3 in Fig. l.

The operating members of the machine are enclosed in a two-part hood, the one part I of which, being of a substantially conical shape, forms the machine frame and is provided with a base 2 for the securing of the machine to a substructure or a wall, and the other part 3 of which forms a cover consisting preferably of some transparent artificial resin or the like, said cover being formed into a shaving box 4 to collect the shavings formed in the sharpening operation, as well as into a sleeve-shaped holder 5 for the pencil 6. Part 3 is connected to part I by means of a bayonet coupling comprising pins 1, 8 arranged on part 3 and slots provided in part I and adapted to be engaged by the pins 1, 8. To facilitate the arrangement of the machine on a horizontal substructure as well as on a vertical wall, in a manner such that the shavings may be collected in the shaving box 4 in both positions of the machine, two pairs of a bayonet slot are preferably 2 Claims. (01. 120 -93) provided in part 2 in positions angularly displaced by so that part 3 may be angularly adjusted relatively to part I in a corresponding manner. To facilitate this shifting of part 3, without alter.- ing the location of the pencil relatively to the knife; parts I and 3 are united with each other throughcylindrical portions 9 and I0 coaxial.

with the axis of the pencil or pencil holder.

The rotating sharpening member consists of an irregularly shaped body II provided with a conical recess I2 for the pencil point I3 opposite the pencil holder 5, said recess being provided at I4 with an incision extending along a generatrix, beside which incision the knife I5 is arranged in suchmanner as to be permitted to operate upon the'pencil point along the portion thereof accessible through the incision. The knife l5, which consists of a plane rim of teeth formed as a cutter, is secured on a shaft I5 rotatably mounted in a holder ll, which is removably connected with the sharpening member I I by means of screws L8. The sharpening member II is rigidly connected with a driving shaft l9 mounted in part I, said driving shaft permitting of being rotated by means of a manually operable crank 20. At the opposite end, the sharpening member II is rotatably mounted on the pencil holder 5, which is for this purpose provided with a metallic bearing sleeve 2I. The driving shaft I9 and the pencil holder 5 are thus coaxially arranged. To attain the requisite balance in the rotating system, the sharpening member H is provided with a counterweight 22 adapted to balance the, weight of the knife holder I1 and the parts mounted thereon.

The knife I5 is adapted to be driven from the shaft I9 by means of a planet gearing comprising a bevel gear 23 rigidly secured on the knife shaft IE, and a plane rim of teeth 24 rigidly secured in part I and adapted to engage the gear wheel 23. When the crank 20 is rotated, the sharpening member II with the knife holder I! and the parts mounted therein will rotate with the driving shaft I 9, the gear wheel 23 being thus caused to roll on the toothed rim 2d. Consequently, the knife holder I! Will perform a rotary motion about the pencil, while the knife is simultaneously caused to rotate in the holder. If the pencil 6 is then retained in the holder, the point of the pencil will be operated upon by the knife I5 about the whole circumference of the pencil, so that a conical shape will be imparted to the pencil point in correspondence to the recess I2.

The signalling means consists of a bell 25 and a clapper 26. The bell 25 is secured in the frame pencil comes into the position in which the sharpening of the lead 32 is entirely or approxi mately completed. The tongue 29 will thus .be swung about the screw 30 through the influence of the pencil point against the action of a spring 33, through which the signalling mechanism is normally kept in inoperative position. When the ing therefor, in combination a bell mounted on tongue 29 is actuated by the pencil point in the manner set forth, the signalling mechanism is brought into the position indicated by chaindotted lines in Fig. 2, an arm 34 bent outwardly from the piece of sheet-metal 21 being thus brought into a position such that the outer end thereof will, upon continued rotation of the shaft of the pencil sharpener, hit the heads of a number of securing screws 35, which in the example shown are four in number, and by means of which the toothed rim 24 is secured in the frame I. When the arm 34 strikes'against said screw heads, a swinging movement is imparted to the clapper 26, the bell 25 being thus actuated ,to give a signal, which indicates that the sharpening of the pencil is finished.

Obviously, the construction and the arrange ment of the signalling means may be modified in various ways. Thus the signalling mechanism may be arranged to be operated by a spring, which is normally locked, and which is triggered by the point of the pencil, the tensioning of the spring being then effected by the driving means of the machine, for example.

What I claim is:

" 1. In a signal device for a pencil sharpener having a rotary sharpening element and a housing therefor, in combination, a bell mounted on the housing coaxially with the sharpening element, signal operating means pivotally mounted on the sharpening element and extending across the path of the pencil point as it is fed during sharpening, a clapper resiliently mounted on said operating means, said clapper having an extension thereon adapted to make contact with stationary portions of thehousing when said signal operating means is pivoted to cause said clapper to oscillate in a direction perpendicular to the feedingumovement of the pencil and resilient 'means for holding said signal operating means in its'inoperated position.

2. In a signal device for a pencil sharpener having a-rotary sharpening element and a housthe housing coaxially with the sharpening element, a signal operating means pivotally mounted .on the sharpening element and extending across the path ofjth'e pencil point as it is fed extending outwardly therefrom and adapted to REFERENCES CITED SThe following references are of record in the fileoffthis patent" g V "FOREI N PATENTS Number Country Date 573,095 Germany' c Mar. 27, 1933 

